The subject invention relates to a multi-layer reflective insulation system and to a multi-layer reflective insulation roll product with air space separation media therein that is used in the multi-layer reflective insulation system. With its air space separation media, the multi-layer reflective insulation roll product of the subject invention requires no physical manipulation by the installer at the job site to activate the insulation roll product so that the product achieves its specified thermal performance.
Many manufacturers of reflective foil insulation systems provide multi-layer reflective insulation products that can be stapled onto the faces of the framing members forming the cavities of a building envelope. The radiant barrier facing material of U.S. Pat. No. 5,918,436 is an example of such a multi-layer reflective insulation product. These multi-layer insulation products are typically stapled onto the framing member faces in the same way that kraft paper faced fiberglass batt products are stapled in place. These multi-layer reflective insulation products have a plurality of reflective sheets, e.g. thin low emissivity aluminum foil sheets or thin low emissivity aluminum foil-kraft paper sheets. The reflective sheets of these multi-layer reflective insulation products have central field portions that are not bonded to each other and lateral edge portions that are bonded together to form the stapling flanges of the product. The stapling flanges of these products are typically formed by folding excess kraft paper back over itself at the lateral edges of the products so that a 1.0 inch to a 1.5 inch wide flange exists on each lengthwise edge of the product. The widths of the central field portions of the reflective sheets of these products differ from each other and typically some of the reflective sheets have folds therein so that the adjacent sheets of the product lay on each other for packaging and handling prior to installation. Since the existence of air spaces between the reflective sheets of these products plays a critical role in the ability of these systems to exhibit the claimed thermal performance (thermal resistance value or R-value), most of these products must be physically manipulated during the installation process by pulling on the stapling flanges or by shaking the products to separate the reflective layers so that one or more air spaces exist between the reflective layers. If the installers do not create the required air spaces between the reflective layers of these products to activate the products by physically manipulating the products during the installation process, thermal short-circuiting will exist between the reflective sheets of these products that reduce the ability of these products to reduce heat flow through the products. When applying these products to the framing members of building envelopes, the existence of non-standard cavity widths in the building envelopes poses another problem for the installers, which can reduce worker productivity and decrease the thermal performance of the products. Where the cavity widths to be insulated with these reflective insulation products are less than the standard width for such cavities and reflective insulation products, these multi-layer reflective insulation products may have to be cut lengthwise to reduce the widths of the products to approximate the widths of the cavities. Since many of these multi-layer reflective insulation products have paperboard tabs or folded pleats near the stapling flanges to aid in the physical manipulation and activation of the products at the job site, cutting away the activation mechanisms of these products to reduce their widths makes the physical manipulation and activation of these products time consuming and difficult if not impossible so that typically, either no air spaces are formed or air spaces are improperly formed between the reflective sheets of the products.